$$A= \left[\begin{matrix} 1 & 2 & 3 \\2 & 2 & 4 \\-1 & 3 & 2 \end{matrix}\right]$$
$A≔\left(\begin{matrix}1&2&3\\2&2&4\\-1&3&2\end{matrix}\right)$
$\left[\begin{array}{rrr}-8 & 5 & 2 \\ -8 & 5 & 2 \\ 8 & -5 & -2\end{array}\right]$
$A_{11}=\left|\begin{array}{rr}2 & 4 \\ 3 & 2\end{array}\right|=-8$
$A_{12}=-\left|\begin{array}{rr}2 & 4 \\ -1 & 2\end{array}\right|=-8$
$A_{13}=\left|\begin{array}{rr}2 & 2 \\ -1 & 3\end{array}\right|=8$
$A_{21}=-\left|\begin{array}{rr}2 & 3 \\ 3 & 2\end{array}\right|=5$
$A_{22}=\left|\begin{array}{rr}1 & 3 \\ -1 & 2\end{array}\right|=5$
$A_{23}=-\left|\begin{array}{rr}1 & 2 \\ -1 & 3\end{array}\right|=-5$
$A_{31}=\left|\begin{array}{rr}2 & 3 \\ 2 & 4\end{array}\right|=2$
$A_{32}=-\left|\begin{array}{rr}1 & 3 \\ 2 & 4\end{array}\right|=2$
$A_{33}=\left|\begin{array}{rr}1 & 2 \\ 2 & 2\end{array}\right|=-2$
$\left[\begin{array}{rrr}-8 & -8 & 8 \\ 5 & 5 & -5 \\ 2 & 2 & -2\end{array}\right]$
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